[MS-SQL] 전화번호의 특수문자 다 걸르기 function

USE [DB]
GO

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

-- =============================================
-- Description: 전화번호의 특수문자 다 걸르기
-- =============================================
CREATE FUNCTION [dbo].[fnAPhoneNo]
(
 @phone varchar(100)
)
RETURNS varchar(100)
AS
BEGIN
 declare @tmp varchar(1), @result varchar(100), @i int
 set @result = ''
 set @i = 1
 while @i <= len(@phone)
  BEGIN
   set @tmp = substring(@phone, @i, 1)
   if ASCII(@tmp) >= 48 AND ASCII(@tmp) <= 57
    set @result = @result + @tmp
   set @i = @i + 1
  END

 RETURN @result
END